1. Field of the Invention
The invention relates to a method for producing a functional layer of a building shell. In addition, this invention relates to a functional shell, produced, in particular, according to the above-mentioned method, as well as a functional layer produced, in particular, according to the above-mentioned method.
2. Description of Related Art
These days, high requirements are set for roofs and façades, i.e., the building shell, because of internal and external factors. External factors are water in liquid form (rain, light snow, melt water, etc.), but also dust, dirt and insects, which penetrate or are driven in through cuts and joints in the cover material. As a result, the subjacent layers can become unacceptably soaked, soiled and/or damaged. Internal factors are, e.g., water vapor convection or diffusion, which can result in unacceptably high levels of melt water or condensation water formation.
To protect the overall structure from the above-mentioned factors, structural composite foils are now installed. For protection from external factors, in general sarking (a layer of boards or bituminous felt placed beneath tiles or other roofing to provide thermal insulation or to prevent ingress of water), below-deck and façade membranes are used; for protection against internal factors, air and vapor traps/barriers are used. Depending on climatic conditions, in this connection the inverse arrangement can also be useful. Depending on the material of the structural composite foils that is used, different properties are necessary, e.g., the water-tightness and the water vapor permeability (sd value), whereby depending on the requirement, a distinction is made among membranes that are open to diffusion (sd value of between 0 and 0.5 m), moisture-variable, vapor-barrier membranes (sd value of between 0.5 and 1,500 m), and vapor-trapping membranes (sd value >1,500 m) (DIN 4108).
In terms of shape, slope, configuration and exposure, roofs are distinguished by, e.g., use, construction, climatic conditions and exposure with respect to building physics. While undisturbed surfaces can be relatively easily covered, there are detail points, e.g., cullises, collars, rising components and connections, as well as intersections, e.g., aerators, cables, etc., to which time-consuming and material-intensive connections have to be made. Also, when installing a structural composite foil, damages of the functional layer by mechanical, chemical and physical stresses can occur. Altogether, it is thus difficult to produce the necessary water-tightness and air-tightness of the structural composite foil.
Previously, connections, detail points, and damage to the functional layer were fixed or repaired by collars or adhesive tapes. The disadvantage of this method is that structural composite foils can be matched to or connected in a time-consuming and difficult way with aids, e.g., nails, staples, adhesive tapes, e.g., with geometrically demanding and/or poorly available details. In addition, in particular, adhesive tapes do not adhere to moist or dusty bases, which are frequently encountered in restoration.
Special difficulties arise even when installing a functional layer in the region of the roof squares. This relates both to the first production of a roof in new construction and roof repair or renovation. The roof squares are formed here by the free spaces between the rafters, whereby a sheathing is provided on the inside of the building, i.e., in the building. The arrangement of a structural composite foil in the roof square and the connection to the sheathing is often difficult and time-consuming.